Starting-switch.



WITNESSES:

J. N. MAHONEY & G. L. CHRISTMANT STARTING SWITCH. APPLICATION FILED FEB. 21. I914.

Patented D00, 4, 1917.

I2 ,3 NT RS ATTORNEY UNITED STATES PATENT OFFICE.

JOSEPH N. MAHONEY, OF WILKINSBUBG, AND GEORGE LIN TON CHRISTIAN, OF SWISS- VALE, PENNSYLVANIA, ASSIGNORS TO WESTINGHOUSE ELECTRIC AND MANUFAC- TUBING COMPANY, A CORPORATION OF PENNSYLVANIA.

STARTING-SWITCH.

Specification of Letters Patent. I

Patented Dec. 4, 1917.

Application filed I'ebruary'fl, 1914. Serial No. 820,279.

Pennsylvania, have invented a new and use ful Improvement in Starting-Switches, of which the followin is a specification.

Our invention re ates to starting devices for motor control and particularly to handoperated starting switches of the type that has a plurality of fixed contact members adapted to be engaged successively by a movable contact member, such as a knifeswitch blade.

One of the objects of our invention is to provide a switch of the above indicated type with means for stopping the movable contact member in each of its correct successive positions. The movable member is thus prevented from making the contacts too rapidly and an appreciable interval of time is insured between the stages of current increase.

A further object of our-.'invention is to provide means for readily releasing the stop, such means being controlled by the operators hand that grasps the switch handle.

A knife switch equipped with our invention and having four steps or stages of current increase is shown in the accompanying drawing, in which Fi re 1 is a front elevational view of the switch. Fig. 2 is a side elevational view of the same showin the switch in its fourth, or fully-closed position. Fig. 3 is a horizontal sectional view taken along the line 111--111 of Fig. 1 and showing a pair of the contact clips as seen from below. Fig. 4. is a detail view showing the first position of the latch, Fig. 5 is a similar view showing the second position of the latch, and Fig. 6 is a similar view showing the third position of the latch.

Referring to the drawing, a set .of four knife blade members 1 is pivoted at 2 to a support 2" on the base 3, 1n 0 erative relation to four pairs of contact ellps l, 5, 6 and 7 which are also mounted on the base 3 and are of different lengths and so disposed that the knife blade members may en age them successively. The switch is manua ly opened and closed by means of a handle 8 in the ordinarzmanner. Current is supplied to the kni e blade members through a terminal 9, and each pair of contact clips is connected, through the base 3, to a terminal, one of which, designated by the numeral 10, is shown attached to the clip 7. The parts thus far described are well known in the art.

We provide the switch with a sto to insure that the switch blades sha make proper contact with each set of clips, and, at the same time, to prevent the blades from passing too rapidly from one set of clips to the next. In the embodiment of our invention shown in the drawing, such stopping device comprises an L-shaped detent 11 pivoted at 12 to a support 12 on the base 3 adjacent to the pivot support 2 of the blades. The lower arm 13 of the detent is provided with a notch adapted to engage the pivot 2 of the blades. This arm 1s pressed outwardly from the base byia spring 14 and the detent is thus given a tendenc to rotate about its pivot 12, the extent 0 its rotation being limited by the contact of the notch on the arm 13 with the blade pivot 2. The upper and outer end of the detent 11 is provided with a notch 15 that is ada ted to be engaged by fixed stops 16 secure to the blades 1 when the detent is pressed outcollars 20 and 21 that cooperate, respectivel with a stop 22 and the stops 16 which are xed on the switch blades.

In the open position of the switch, the

switch blades are out of contact with all of the contact clips and the detent 11 is maintained in its outward position by the spring 1 L When the switch is closed, the blades 1 first make contact with the clips 4:, and the engaging parts are so adjusted that, when the correct contact point is reached, the stop 16 engages the end of the detent 11 in the manner shown in Fig. 4. In order to release the stop, the operator presses the button 18 and thus moves the rod 17 until its end is even with the end of the stop 16. This depresses the detent sufiiciently to enable the blades to be moved to their second position, in contact with the clips 5, when the notch 15 on the detent 11 will engage the downwardly projected end of the rod 17, as shown in Fig. 5. The operator then releases the button 18, whereupon the rod 17 is withdrawn to its original position, under the influence of the spring 19. The blades may then be moved to their third position, in contact with the clips 6, the relation of the engaging parts being shown in Fig. 6. A second depression of the button 18 will serve to depress the detent 11 sufficiently to enable the stop 16 to pass it and permit the switch to be moved to its fully closed position, which is shown in Fig. 2.v

It is to be noted that the blades, in their first movement, are positively prevented from moving past their correct initial contact points, even if the operator should press the button 18 as he moves the switch to its first position. In such a case, the end of the detent 11 would merely engage the end of the rod 17 instead of the stop 16.

While we have illustrated our device as I applied to a knife switch having four blades and having an operating rod 16 centrally disposed with respect to the blades, it is to be understood that our invention is not restricted to this structure, but that it may be applied to any type of switch or other, current-controlling device in which it is de .sired to have several successive closing stages. Only such limitations are to be imosed upon our invention, therefore, as are indicated in the appended claims.

We claim as our invention:

1. A switch comprising a base, a movable contact member pivotally mounted thereon, a plurality of stationary contact members, a detent pivotally mounted on the base, a stop carried by the movable member and adapted to engage the detent and a movable springrestrained stop also carried by the movable member and adapted to coeperate with the detent and the stop whereby successively depressing and releasing the spring-restrained stop permits the movable contact member to be moved successively into engagement with the stationary contact members.

2. A switch comprising a movable contact member, a plurality of stationary contact members, a stop fixedly mounted on the movable contact member, a spring-restrained detent mounted on a stationary member, various portions of the said detent being adapted to be engaged by the said stop on the movable member, and a manually operated spring-restrained means mounted on the movable contact member for so moving the detent that the stop is permitted to disengage one portion of the same and engage another portion of the same when the movable contact member is actuated.

3. A switch for current control comprising a base, a movable contact member pivoted thereto, a plurality of fixed contact members on the base adapted to be successively engaged by the movable member, and means for releasably holding the movable member in each successive contact position said means comprising a detent pivoted to the base and a manually operated stop car ried by the movable member and adapted to engage the detent.

4:. A switch for current control comprising a base, a switch blade pivoted thereto, a plurality of contact members on the base adapted to be successively engaged by the blade, and means for stopping the blade in each successive contact position, said means comprising a spring-pressed detent pivoted to the base and a stop carried by the blade and adapted to engage the detent.

5. A switch comprising a base, a switch blade pivoted thereto, a plurality of contact members on the base adapted to be successively engaged by the blade, means for stopping the blade in each successive contact poslt-ion, said means comprising a detent pivoted to the base and a stop carried by the blade and adapted to engage the detent, and means mounted on the blade for releasing the said stop from the said detent.

6. A knife switch comprising a base, a switch blade pivoted thereto, a plurality of contact members on the base adapted to be successively engaged by the blade, means for stopping the blade in each successive contact position, said means comprising a detent pivoted to the base and a stop carried by the lade and adapted to engage the detent, and means mounted on the blade for releasin the said stop from the said detent, sai means comprising a longitudinally movable rod and means for yieldingly holding the rod out of operative position.

7. A knife switch comprising a base, a switch blade pivoted to the base, a plurality of contact members adapted to be successively engaged by the switch blade as the latter is moved to its closed position, means for holding the blade in each of its successive positions, said means comprising a stop secured to the blade and a spring-pressed detent pivoted to the base and having a notch for engagement with the said stop, and manually operated means for releasing the latch.

8. A knife switch comprising a base, a switch blade pivoted to the base, a plurality of contact members adapted to be successively engaged by the switch blade as it is moved to its closed position, means for stopping the blade in each of its successive positions, said means comprising a detent pivoted to the base and a fixed stop secured to the blade, means for releasing the latch comprising a longitudinally movable rod secured to the blade with its end ad1aeent able contact member is stopped in engagcto the said stop, and meansofor yielc'ingly ment with each stationary contact member. holding the rod in a retracted position. In testimony whereof, we have hereunto 9. A switch comprising a base, a movable subscribed our names this 14th day of Feb., 1i 5 contact member, a plurality of stationary 1914.

contact members, a spring-pressed detent OSEPH N. HAHONEY plvoted to the base, a stop earned b the J movable contact member and relatively inmr- 9mm}! able means mounted on the movable contact Witnesses:

10 member for moving the detent to such posi- SCHUYLBB M. Hun

tions with respect to the stop that the mov- B. B; Hmns. 

